In the construction of internal combustion engines, engine starting has been improved by providing means for releasing the pressure in the combustion chamber during the compression stroke. Such compression release mechanisms are intended to permit easier cranking of the engine to provide for easier starting. In the past such pressure release mechanisms have comprised mechanical pump valves which are either manually or automatically actuated during starting of the engine.
Attention is also directed to the U.S. Illmer Pat. No. 2,072,623, issued Mar. 2, 1937; the U.S. Brehob Pat. No. 4,154,207, issued May 15, 1979; and the U.S. Currie et al. Pat. No. 3,667,443, issued June 6, 1972.